There are several metabolic diseases of human and animal glucose metabolism, eg., hyperglycemia, insulin dependent diabetes mellitus, impaired glucose tolerance, hyperinsulinemia, and insulin insensitivity, such as in non-insulin dependent diabetes mellitus (NIDDM). Hyperglycemia is a condition where the blood glucose level is above the normal level in the fasting state, following ingestion of a meal or during a glucose tolerance test. It can occur in NIDDM as well as in obesity. Hyperglycemia can occur without a diagnosis of NIDDM. This condition is called impaired glucose tolerance or pre-diabetes. Impaired glucose tolerance occurs when the rate of metabolic clearance of glucose from the blood is less than that commonly occurring in the general population after a standard dose of glucose has been orally or parenterally administered. It can occur in NIDDM as well as obesity, pre-diabetes and gestational diabetes. Hyperinsulinemia is defined as having a blood insulin level that is above normal level in fasting state or following ingestion of a meal. It can be associated with or causative of hypertension or atherosclerosis. Insulin insensitivity, or insulin resistance occurs when the insulin-dependent glucose clearance rate is less than that commonly occurring in the general population during diagnostic procedures.
A number of compounds have been tried to alleviate symptoms associated with glucose metabolism disorders. For example, guanidine, monoguanidine and biguanidine compounds have been shown to produce hypoglycemia. Watanabe, C., J. Biol. Chem., 33:253-265 (1918); Bischoff, F. et al., Guanidine Structures and Hypoglycemia, 81:325-349 (1929). However these compounds were shown to be toxic. Biguanide derivatives, e.g., phenformin and metformin, have been used clinically as antidiabetic agents. Some members of this class continue to be used today, while others have been withdrawn from the market. Schafer, G., Diabetes Metabol. (Paris) 9:148-163 (1983). Gamma-guanidinobutyramide, also known as Tyformin, and its salt derivative, Augmentin, were investigated as potential anti-diabetic agents from the mid 1960's to mid 1970's. While Augmentin produced hypoglycemia, it was reported to have major undesirable side effects such as hypertension and circulatory collapse. Malaisse, W. et al., Horm. Metab. Res., 1:258-265 (1969); ibid, 3:76-81 (1971).
British patent 1,153,424 discloses the use of certain esters and amides of guanidino-aliphatic acids in the treatment of diabetes mellitus where hyperuremia is present. The patent does not disclose that these compounds have an effect on hyperglycemia or any other symptom or pathological state related to disease. Canadian patent 891509 discloses the use of esters and amides of guanidinoaliphatic acids were disclosed for treating hyperuremia and hyperglycemia in diabetes mellitus.
British patents 1,195,199, and 1,195,200 disclose the use of guanidino alkanoic acids or their amides or esters for the treatment of hyperglycemia occurring in diabetes. A variety of British patents (1,552,179/1,195,199/1,195,200/1,552,179) describe the low potency of the guanidino alkanoic acid derivatives as single agents but describe their use in combination with other modalities.
Aynsley-Green and Alberti injected rats intravenously with beta guanidino propionic acid, arginine, guanidine, 4 guanidinobutyramide and 4 guanidinobutyric acid. Arginine and beta guanidino propionic acid stimulated insulin release but did not affect glucose levels. Also the treatment of animals with large amounts of beta gunidino propionic acid for several weeks was shown not to affect glucose levels, Moerland, T. et al., Am. J. Physiol., 257:C810-C816 (1989). Under different conditions beta gunidino propionic acid was shown to have an effect as described later. The two other compounds did stimulate insulin release but increased glucose levels. Aynsley-Green, A. et al., Horm. Metab., 6:115-120 (1974).
It is an object of the present invention to provide methods for treatment of metabolic diseases that relate to glucose level regulation by administering to an afflicted individual an amount of a compound or compounds which modulate one or more of the structural or functional components of the creatine kinase/creatine phosphate system sufficient to prevent, reduce or ameliorate the symptoms of the disease. These compounds are collectively referred to as "creatine compounds." The experiments described herein demonstrate that the creatine kinase system is directly related to control of blood glucose levels in animals. Creatine analogues are shown herein to be effective hypoglycemic agents for treatment of glucose metabolic diseases.